Spectrum dialog box
The TV80 offers a spectrum analyser that shows the signals from each hydrophone. The Spectrum dialog box presents an overview of the current hydro-acoustical conditions. You can use this function to "see" the signals from each hydrophone, as well as the background noise.
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How to open
This dialog box is opened from the Setup menu.
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Description
The quality of the acoustic communication link between the sensors and the receiver can be challenged by noise. When noise appears in the same frequency range as the sensors are using for their communication, the resulting information may be unstable or unreadable. The graph in the Spectrum dialog box provides you with information about the background noise and the signal strength in the selected frequency band. With this information you can identify noise and find the "cleanest" frequencies.
On the top and bottom parts of the graph, the channel identifiers correspond to the relevant receiver channel. With the channel identifiers you can easily see in which channels you have signals and noise.
•  The upper scale (PI) identifies the channels for the PI Family receivers.
•  The bottom scale (SR) identifies the channels for the SR Family receivers.
The graph plots data using a 16 colour palette. Red colour corresponds to the maximum value defined, while blue is the minimum.
Details
Hydrophone input
Select a hydrophone from the list provided. The graph shows you signals coming from the selected hydrophone.
Max Value
Define the maximum dB value you want to be shown in red colour.
Step Size
Define the size (in decibels) of the step between two colours.
Screen Captures
To save an instantaneous image of the current frequency spectrum, select Screen Captures in the Spectrum dialog box. A small dialog box opens to show you the destination folder of the image file.
Context sensitivity
The Spectrum dialog box is only available if an SR type receiver unit or replayer have been added to your TV80.